Short-term and Long-term Debt - Mega Bank Credit Facility (Details)	Jun. 17, 2023	Apr. 25, 2022 USD ($)	Sep. 13, 2021 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Apr. 25, 2022 TWD ($)	Sep. 13, 2021 TWD ($)
Short-term Debt [Line Items]
Long-term debt				$ 120,179,000	$ 147,618,000
Revolving Credit Facility | Mega Bank Credit Facility | Mega Bank | Line of credit
Short-term Debt [Line Items]
Credit facility, maximum borrowing capacity			$ 43,200,000	$ 38,700,000	$ 40,400,000		$ 1,200,000,000
Drawdowns percentage (as a percent)			80.00%
Period after first drawdown principal payments commence			2 years
Principal payment term			3 years
Revolving Credit Facility | Mega Bank Credit Facility | Mega Bank | Line of credit | Minimum
Short-term Debt [Line Items]
Interest rate (as a percent)			0.645%	1.40%	1.02%		0.645%
Revolving Credit Facility | Mega Bank Credit Facility | Mega Bank | Line of credit | Maximum
Short-term Debt [Line Items]
Interest rate (as a percent)			0.845%	1.60%	1.22%		0.845%
Revolving Credit Facility | Omnibus Credit Authorization Agreement | Mega Bank | Line of credit
Short-term Debt [Line Items]
Credit facility, maximum borrowing capacity		$ 20,000,000
Revolving Credit Facility | 2022 Credit Authorization Agreement | Mega Bank | Line of credit
Short-term Debt [Line Items]
Interest rate (as a percent)		0.75%		2.55%	1.85%	0.75%
Credit facility, term		120 days
Interest rate, stated percentage		0.90%				0.90%
Debt instrument, term, TAIFX offer		6 months
Debt instrument, fee amount						$ 400
Credit facility, remaining borrowing capacity				$ 20,000,000
Outstanding borrowings				0	$ 3,500,000
Revolving Credit Facility | 2022 Credit Authorization Agreement | Mega Bank | Line of credit | TAIFX OFFER
Short-term Debt [Line Items]
Credit facility, basis spread on variable rate (as a percent)		0.23%
Basis spread on variable rate, divided by amount		0.946
Revolving Credit Facility | 2022 Credit Authorization Agreement | Mega Bank | Line of credit | US Basic Loan Rate
Short-term Debt [Line Items]
Interest rate (as a percent)		0.10%				0.10%
Revolving Credit Facility | 2023 Credit Authorization Agreement | Mega Bank | Line of credit
Short-term Debt [Line Items]
Outstanding borrowings				$ 0
Revolving Credit Facility | 2023 Credit Authorization Agreement | Mega Bank | Line of credit | Minimum
Short-term Debt [Line Items]
Credit facility, term	120 days
Revolving Credit Facility | 2023 Credit Authorization Agreement | Mega Bank | Line of credit | Maximum
Short-term Debt [Line Items]
Credit facility, term	180 days